Motor mount for motorized bicycles



Nov. 22, 1949 T. A. WOOLSEY ET AL MOTOR MOUNT FOR MOTORIZED BICYCLES Filed Nov. 28, 1947 INVENTORS Patented Nov. 22, 1949 MOTOR MOUNT FOR MOTORIZED BICYCLES Theodore A. Woolsey, Pasadena, and Robert A. Webster, Santa Monica, Calif., assignors, by mesne assignments, to Jack & Heintz Precision Industries, Inc., Cleveland, Ohio, a corporation of Delaware Application November 28, 1947, Serial No. 788,768

14 Claims.

This invention relates to motorized bicycles, and, in particular, to motorizing attachments for bicycles.

The general object of this invention is to provide a motor mount that is adapted to be attached to most any .standard balloon tired bicycle, for mounting a small gasoline engine or the like in the central space between the bars of the bicycle frame.

While bicycle frames are to a large extent standardized, the shape and dimensions and angularity of the tubular bars of the frame. vary to a considerable extent. For example, the forward diagonal bar or supporting bar which extends from the front fork bearing tube down to the crank bearing, is in some cases straight and in other cases downwardly arched, with its intermediate portions lying several inches lower than the corresponding portion of the straight bar. The difference between the positions of the two bars with relation to the upright bar which extends from the seat post down to the crank bearing, may range as high as four inches.

One of the objects of the invention is to provide a motor mount which is universally attachable to the frame of any bicycle. A further object is to provide a motor mount of standardized construction for most all bicycles, capable of supporting an internal combustion engine within the triangular space between the cross bar, the supporting bar and. the upright bar of a bicycle frame, utilizing such space to the best advantage for accommodating the motor and the drive from the motor to the rear wheel. In general, this means that the motor must be supported at about the same height in each case, but it may be necessary in some cases to place the motor farther forwardly or rearwardly than in other cases in order to properly center it between the supporting bar and the upright bar of the frame and obtain proper belt tension. The invention meets the problem of adapting the standardized mount to all types of frames by providing a mounting base having at least one end provided with a fork that embraces and is connected to a clamp which in turn is attachable to one of the two diagonal bars of the central frame. The furcations of such fork are adapted to straddle such bar. Where the distance between these two diagonal bars is short, the furcations of the motor base may project beyond the bar embraced by them. Where the distance between the two bars is greater, the ends of the furcations may extend just to the respective bar without straddling it. Longitudinal slots in the respective furcations provide for adjustment of the connection between the fork and a part that is fastened to the frame bar. The in vention maintains the length of these slots at a minimum by providing for pivotal adjustment. be-

tween the fork and the bracket clamp, whereby,

. the position of the latter may be substantially reversed so as to increase the range of adjustment provided by the slots.

A further object of the invention is to provide for adjustment in a vertical direction simply by shifting the bracket clamp up or down upon the bar to which it is attached. Since the bar is diagonally arranged, such shifting requires a corresponding horizontal adjustment between the bracket clamp and the motor base, and this is an additional reason for the provisionfor maximum horizontal adjustment by the combination of the slot and the reversibility of the attachment part.

A further object is to provide a motor mount adapted to coordinate, to the best advantage, the positioning of the motor, the exhaust pipes thereof, and the drive mechanism. A further object is to provide for a motor having a maximum area of cooling fin surface. In this respect, the invention takes advantage of the lesser inclination of the supporting bar as compared to the upright bar to place the forward cylinder fairly close to the supporting bar, with the forward exhaust pipe passing downwardly through the forward fork of the motor base, while the rear cylinder is spaced a greater distance from the upright .bar and the rear exhaust pipe passes downwardly past the side of the motor base. The baseis therefore provided with an arched form on the side where the rear exhaust pipe passes it.

Another feature of utilizing maximum space for the engine is to position the engine as high as is permitted in a double frame (frame with two cross bars). To this end, the forward fork of the motor brace is inclined downwardly and forwardly, such inclination also providing greater clearance for the forward exhaust pipe in passing through the forward fork.

Other objects will become apparent in the ensuing specifications and appended drawings in which:

Fig. 1 is a side view of portions of a motor bicycle embodying our invention;

Fig. 2 is a vertical sectional view taken on the line 2-2 of Fig. 1;

Fig. 3 is a detailed sectional view taken on the line 3-3 of Fig. 1; and

Fig. 4 is a detailed sectional view taken on the line 44 of Fig. 2.

To illustrate one application of the invention,

we have shown in Fig. 1, in dot-and-dash lines, a bicycle having a double bar type frame including cross bars 5 and 6, front fork bearing 1, a supporting bar 8 extending diagonally downwardly and rearwardly from the front fork bearing 1 to the crank bearing 9 and joined to the forward end of the lower cross bar 6, and an upright bar It] extending upwardly from the crank bearing 9 and joined to the rear ends of the cross bars 5 and 6. We have also shown,

a diagonal bar 8, as indicated'in Fig. 1.

in dotted linesythe relativet-position of aodownwardly arched supporting bar 8a.

The motor mount of our invention is adapted to be attached to either of the two framesxindicated, and to support a .motor insubstantially the same relative position in either case. The motor mount base, which is indicated;generally at H, has a central platforming a; front fork portion I3, and a rear-fork portion I4. In the platform I2 are three longitudinally-elongated slots I5, I6 and I! which receive cap screws IB for securing to the platform I2 the crank case portion I9 of the engine which has cylinder heads 20 and 2|. The cap screws lll are extended upwardly through the platform I2 from beneath*and are threaded into suitableibosses "in'the crank case I9.

The engine is designed to utilize the upper half Iofthe triangular space between the-.bars 6, 8 and'II'I, and tobe positioned as "closely as pose sible to the horizontal bar 6, in order -that an 'engine of maximum length may be accommodated.- Accordingly, the motor base' il will-usually be positioned :about midway, vertically, between the horizontal .bar 6 and the crank bearing 9. At this midlevel, the horizontal distance "between" the .bars 8' and I may be as much as three or four inchesgreater in the case of the bicycle having the downwardly arched bar 8a than in the case of thebicycle having the straight Consequently, an adjustment of three to four inches or more is required in order that the mount may be universal; Adjustment is provided for by constructing the fork I3 ofl ample length to'str-a'ddle the bar 8 and to projectbeyond it sufiici'ently to reach positions that would be occupied by the bar 8a, and by providing for connecting the fork to the diagonal bar by the following means:

The twofurcations ofthe fork I3 are provided;

with slots 22 extending. longitudinally therein. A bolt 23 extends through the slots 22nand through asleeve 2 4 formedon a 'member'l25. of a bracket clamp ZG'that is designed to -embrace'and be clamped upon the-bar 3 (or 8:1, as-ntheicase may be). The clamp-26 comprises tl1e'jaw'25, a second jaw 2'1, and a pair of clamp bolts28v which extend through apertured ears 29 at the.-respecwtive-ends of each jaw. Each jaw 25, 21 confines a synthetic rubber sleeve 1 3i which providesz a I I resilient shock mount for the unit.

The bolt 23 provides apivotal'connectionibetween the bracket -clamp-26"and.= fork I 3; around which theclamp 26 may be adjusted soasto'con- -form to the exact angularity. otthe'bar B'in 'any.

bicycle. The invention provides for reversal; of theposition of "the clamp-26 from that shown in full lines in Fig. 1-, in which it extends upwardly .and forwardly and-engagesthesdiagonalrbar 8 forwardly of the center of intersection .oftheaxes, of-the bar 3 and platform II, tozcthe position shown in dotted linesin Fig. lnin whichituextends rearwardly and engages the bar .8111 at a point rearwardly of the inters'ection oit-the'zaxes of the bars 8a and motor-base II.- .Suchrprovi.- sion-for reversing the position ofzthe' clamp: 26 makes it possible to adjust the -mount' to either of the two'frames' withoutthenecessityofashaving the slot 22 the full length of-the -difrerence between the positions of the bars 8 and BarespeclOwzlothing becoming caught on the projecting ends of thefurcations.

Therear fork I4 is connected to the upright bar ID by means of a clamp 26' which is prefera- -*bly'identical in construction with the clamp 26 in order to provide for standardized parts and :therebyr educe production. costsji The clamp 26' is connected to-theimotoribase' IIJ'by albolt 23 which extends through slots 22' in thefurcations o'f thezfork I4.:..-Slots 22 iprovide for-:additional :extent ofla'djustment where necessary.

' :The' finszon the-underside of the. cylinder'heads ZD-and ZIIareshortened along? diagonal lines, as ---at-3I-, to fit=the inclination of the bars 8' and I 0.

Such foreshortening increases the;.=t'ota1 length 0'f theimot0r that .-can be.-accommodated in the central 'space' of the frame.

The-exhaust from the-.two cylinders I of the engine is .discharged'ithrough1 exhaust pipe elbows 32 and 33: extendingrdownwardly from the resp'ective cylinders,iicurving rearwardly and con- I tinuingvh'orizontallynin the exhaust pipes 34 and 35=respectively.. .The fork" I3 is of sufficient depth toxre'ceive the elbow 32lwhich:extends downward- 1y: therethrough.

35 I Referring now to Fig; 2-, it will .be noted that the platform. I2 is 'ofi-set: to one-side' of the longitudinal axis ofthe motor-base I lxwhichnbisects the spacesbetween the furcations of. the forks 1 lI 3' and l 4. correspondingly, the rear extremity 0 (indicated! at 369 ofathe space embraced by the fork lii is 'oifset' from said axis. Thisarrange- -ment provides :cfo'rlocating the longitudinal axis 5 f of th'e: motor at' one side of =the central plane of the-bicycleframe so asto provide-space to' accommodate'ponithe. other :side of: the bicycle; the llflywheel'f 31. and: the drive mechanism: 38,1 .The :1 flywheel: 31 is-Ldisposedsubstantially in the: plane nzofnthe' framef whileothe drivemechanismi 38 is docatedz: in. amplane immediately I alongside ..the

r=frame.. :Ihus; a rmaximum'c percentageof.;the spac'e' withinthe central-portion of the .frame is utilized, and maximum transverse compactness of the engine and. drive; mechanism is provided, making it easy :forthelegs orthe rider to-straddle s i-the motor and drivemechanism.

at It: may besnoted. atthis :point .that r. the .three .1 slots I5;-'I 6 and I l are arranged in triangular for- ::amation-,:with the-slots l5ra'ndr I6 substantiallyion ...-the' 'longitudinal' axisl O'fizthe motorhase II .:and

ithezs'lot I'I'l'nearr-the'. extremity of'the'offset side of I thew-base; :This :triangular: arrangement" permits theioffset side ofathebase to be inclined inwardly to aconsiderableextent. so as to provide. the re- .acess: 39;..which accommodates the .rear exhaust pipevelbow' 33,- without unduly weakening the -.-base.

:The forward fork:.I3 of .the'base- II is inclined downwardly sand forwardly: asxishown. in r Fig. 1. :JJSllChT; inclination. reduces; the. total necessary i zlength. of the -base';-'since the base meets the bar 8 10112811"a"s=-thecase maybe) at a point nearer to -ith'e=bearing 9 and=therefore= farther to the rear than it would it thezbasewere-straight for its full len'gthZ The downward inclination-also makes it 752possible for th clanip 26 to project upwardly (so as to clear the elbow 32) and yet clear the cylinder head 20.

A combined fuel tank and luggage carrier 4|, embracing the bars 5 and 6, occupies the space immediately above the engine and drive mechanism and cooperates with the beltguard 42 of the latter to hold the clothing of the rider out of contact with the engine and flywheel.

We claim:

1. In a motorizing mechanism for a bicycle having a frame comprising a diagonal supporting bar, an upright bar and a horizontal bar joining the upper ends of the other two bars: a motor mount including a base for attachment to midportions of said supporting bar and upright bar, connecting means for securing the respective ends of said base to said supporting bar and upright bar, said base having an intermediate platform portion to which may be attached a motor having a flywheel and a drive pulley disposed outwardly of said flywheel, said platform portion being offset to one side of the longitudinal axis of said base, whereby to dispose the axis of said motor at one side of the plane of said frame, with said flywheel disposed substantially in the plane of said frame and said drive pulley disposed in a plane closely adjacent the other side of said frame.

2. Mechanism as defined in claim 1, wherein said connecting mean are adjustable longitudinally of said base.

3. Mechanism as defined in claim 1, wherein said connecting means include a clamp and means connecting said clamp to said base for sliding movement longitudinally of the base and for pivotal movement around a transverse axis.

4. In a mechanism for motorizing a bicycle having a frame comprising a diagonal supporting bar, an upright bar and a horizontal bar joining the upper ends of said supporting bar and upright bar: a motor mount including a base having forks at its respective ends and a mounting platform intermediate said forks, a pair of clamps to embrace said supporting bar and upright bar respectively, and a pivotal connection between each commodating its respective clamp in either of two alternative positions extending in directions at least 90 degrees apart.

6. In a mechanism for motorizing a bicycle having a frame comprising a diagonal supporting bar, an upright bar and a horizontal bar joining the upper ends of said supporting bar and upright bar: a motor mount including a base having a fork at one means for connecting the respective ends of said base to the supporting bar and the upright bar respectively, said means including a clamp adapted to embrace one of said bars and to be embraced by said fork, and a pivotal connection between said clamp and said fork for conforming the clamp to the angularity of said one bar and permitting the clamp to assume either of several positions extending from its pivot in different directions so as to'vary the positioning of the clamp with reference to the base in the horizontal direction and thereby vary the adapting of the base to said one bar.

7. Mechanism as defined in claim 6, wherein said pivotal connection comprises a sleeve disposed at one corner of said clamp and transverse to the main axi of the clamp, and a bolt extending through said sleeve and having its ends mounted in said fork.

8. Mechanism as defined in claim '7, wherein the furcations of said fork have longitudinally extending slots therein, receiving said bolt and permitting adjustment of said pivotal connection longitudinally of said base.

9. Mechanism as defined in claim 6, wherein said fork is inclined downwardly and forwardly from said platform, so as to meet said one bar at a closer point than if it were extended in alignment with said platform.

10. Mechanism as defined in claim 6, wherein said platform is offset to one side of the longitudinal axis of said base, thereby to support a motor at one side of the plane of said frame and accommodate a flywheel and drive mechanism on the other side of said plane, with the drive and motor extending substantially the same distance on either side of said plane.

11. Mechanism as defined in claim 6, wherein said fork is of sufiicient depth to accommodate an exhaust pipe elbow extending downwardly therethrough, rearwardly of said clamp.

12. Mechanism as defined in claim 6, wherein said fork extends downwardly and forwardly from said platform and is also extended laterally from one side of said platform so as to offset said platform to the other side with reference to the longitudinal axis of said base, and including a twocycle internal combustion engine mounted on said base at one side of the central plane of said frame and a flywheel and drive mechanism disposed on the other side of said frame with the flywheel interposed between the drive mechanism and the motor and relatively close to the plane of the frame because of the offsetting of said platform.

13. Mechanism as defined in claim 12, including a fuel tank straddling said horizontal bar and occupying the space immediately above said engine, flywheel and drive mechanism, and wherein said drive mechanism includes a guard cooperating with said fuel tank to maintain the clothing of a rider out of contact with said flywheel.

14. Mechanism as defined in claim 1, wherein said base has at its forward end a fork comprising furcations each provided with a longitudinally extending slot, and wherein said connecting means comprises a clamp consisting in two jaws shaped to embrace and engage said supporting bar and a pair of bolts extending through openings in said jaws and arranged to draw them into clamping engagement with said bar, one of said jaws having a sleeve extending transversely to the axis of the clamp, and a bolt extending through said sleeve and having its ends extended through said slots whereby to provide a pivotal and longitudinally extensible connection between said clamp and said base.

THEODORE A. WOOLSEY. ROBERT A. WEBSTER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 656,323 Hansel Aug. 21, 1900 1,967,415 Lesage July 24, 1934 

